Research

Ever wonder why new born infants stay awake and active during night but sleep during day time?

Body clock or Circadian rhythm is what enables us to synchronise the working of our body with the day and night. The actual ‘clock’ is a cluster of around 10,000 nerve cells that lie buried deep within a part of the brain called the hypothalamus. Light coming in through our eyes ‘trains’ the body clock to keep in time with day or night and resets it slightly every day.

Your body has an internal clock that makes you feel sleepy at night and awake during the day. Even though there are 24 hours in a day, this clock is actually on a slightly longer cycle (24.1 hours).

The production of rhythms is complex. But we can sum things up as follows: special clock genes in the Supra Chiasmatic Nucleus (SCN) switch on which leads to protein production. As these proteins accumulate, along with other chemicals, they switch off the clock genes. The level of proteins then drop to point where the genes are able to switch on again and the cycle restarts. This cycle of switching off and on happens about once every 24 hours. The SCN sends out signals to the rest of the body that vary according to this cycle. The cycle is not just determined by the SCN itself: it responds and adapts to signals from outside the body (principally light and dark) to keep the organism synchronised with the world around it – that is, ticking at the right time.

It is with the stimulation of the SCN, that the pineal gland in the brain produces a hormone called melatonin which tells our body to sleep…..

A newborn’s biological clock is immature. It takes time for a baby to develop his own natural circadian rhythm as it had stayed in dark for 24/7 in the womb for a long time. Sleep patterns develop with time, and as the baby gets older, her biological clock and nervous system matures, which makes it get on a routine.

Then what happens when a person is experiencing a jet lag due to long distance travels? The answer to this is also the same. Bright light can help us to reset our circadian rhythms according with the new time zone.

A recently published American study by Cacioppo and colleagues (2013) analysed responses from nearly 20,000 people who married between 2005 and 2012. They found that more than one-third of marriages in America now begin on-line.

As for the satisfaction – In comparison with more traditional off-line meeting, the on-line couples expressed greater marital satisfaction and were slightly less likely to separate or divorce.

They conclude that online dating is becoming increasingly responsible for the shifts in institution of marriage. How much of this is for good – only time will decide.

You probably have heard of the nature-nurture debate. In the last decade or so, researchers have come to better understand the field of epigenetics and below is an interesting example of this in the link between stress and attachment.

Research indicated that rats raised by mothers who groom and lick them are later better able to cope with stress than pups who were infrequently licked and groomed. What seems to happen is that the brains of well-licked baby rats have been changed.

Basically, there are receptors in the brain that mop up the stress hormone cortisol, thus reducing the effect of stress on the brain. The gene that codes for these receptors is modified by the mothers’ behaviour so that the less pampered pups ultimately have fewer cortisol receptors in their brain.

The bottom line is that the attachment behaviours of the mother appears to alter the young rats’ brains so they cope less well with stressful experience. And this also affects the way the young rats subsequently treat their own babies. Nurture modifies nature. Poor attachment experiences lead to negative effects.